package demo02;

import java.util.ArrayList;
import java.util.Collection;

public class test_2 {
    public static void main(String[] args) {
        Collection<String>list=new ArrayList<>();
        list.add("1");
        list.add("2");
        list.add("4");
        boolean b = list.contains("3");
        System.out.println(b);
        list.remove("1");
        System.out.print(list);
        list.clear();
        System.out.print(list);
        list.add("伙计");
        list.add("油鸡儿困");
        System.out.println(list);
        boolean b1 = list.isEmpty();
        System.out.println(b1);
        int size = list.size();
        System.out.println(size);


    }
}
